One of the major problems that exists in the art of pharmacy is that many patients, particularly young children and older adults, are unwilling and/or unable to swallow tablets, capsules or other solid dosage forms of medication. Liquid cold/sinus preparations are admittedly not novel and numerous commercially available formulations exist in the marketplace. Benadryl.RTM., Vicks.RTM., Sudafed.RTM., Dimetapp.RTM. and others are all well known liquid cold remedies that are easily swallowed and do not possess the problems inherent in swallowing a tablet which causes difficulty for young children and older patients. These cold/sinus remedies vary with respect to what actives are present, but many include a decongestant, an antihistamine, an expectorant, an analgesic and the like either singly or in combination depending upon the relief sought.
The problem that exists with respect to many of these actives is that they are not very soluble in water and therefore require some type of organic solvent such as alcohol for dissolution and dispersion throughout the liquid formulation. Another problem that is inherent with these cold medications is the bad taste of the actives and therefore measures must be taken to flavor the liquid in some way so as to taste-mask the active and prevent its perception by the patient. If these drawbacks are not resolved, high degrees of patient compliance cannot be assured.
Co-pending applications Ser. Nos. 08/072,614 and 08/123,402 disclose and claim non-alcohol cold and sinus medications in which the active antihistamine and decongestant are solubilized through the use of an emulsifier/surfactant which, together with other ingredients in specified ratios yield a product that provides effective relief of cold/sinus symptoms yet still tastes good and imparts a smooth, lubricous mouthfeel.
U.S. Pat. No. 4,892,877 to Sorrentino discloses a cough-sore throat medication comprising an aqueous-based liquid preparation comprising an antitussive such as dextromethorphan and a known topical anesthetic such as phenol. Although water serves as the main carrier in the formulation, an alcoholic co-solvent is also required up to 25%.
U.S. Pat. No. 5,112,604 to Beaurline et. al. discloses a sustained release oral formulation for an active drug, in particular, theophylline, an antiasthmatic. The drug is maintained in an aqueous suspension through the use of a hydrocolloid gum/silicon dioxide suspending agent. A polymeric particle system such as polyvinyl pyrrolidone, polyvinylalcohol, acrylic acid and the like are necessary as a dispersing agent in a 70% sorbitol carrier solution.
The need for using high levels of alcohol as a solvent and as a flavor enhancer in the formulation which serves no therapeutic purpose has recently been questioned in that consumption of alcohol in any form has never been regarded as highly beneficial to ones health. Nevertheless, the conventional carrier for the active and flavor ingredients in most cold/sinus medications is typically a water:alcohol mixture. Generally, the ratio of water to alcohol is in the range of from about 1:1 to about 20:1 and most commonly from about 3:1 to about 10:1. The typical amount of the water:alcohol mixture comprising the cold/sinus formulation ranges from about 50% to about 99.9% of the entire composition by weight. In light of these amounts of alcohol present in most formulations, it is obviously beneficial to make non-alcohol based liquid medications available.
However, it has also come to light that many of those who use antihistamine medications were taking them for allergy relief and were thereby also sensitive to many other potential allergens. It was realized that the inclusion of various dyes for color in these formulations sometimes compounded the allergic reaction and therefore the medication did not necessarily alleviate it. Removal of these compounds would be a further advantage as the absence of dye could not lead to additional allergic reaction. One would expect however, that the previously grape or cherry-colored syrups would lose their aesthetic appeal. Surprisingly, the present invention provides a clear, colorless liquid that imparts a natural, wholesome constituency which can only enhance greater patient compliance.